Our application uses Core Image to apply custom CIFilters to still images and video. I'm running into issues when the supplied image is large enough (>4096) that the image is automatically tiled. The simplest of these to describe is a filter that performs various mirroring effects - backwards, upside-down etc.
The implementation portion of the filter provides a sampler (src) and passes this into the kernel with an roiCallback that uses the destRect, inset by -1 in both dimensions:
return [mirrorsKernel applyWithExtent:[src extent] roiCallback:^CGRect(int index, CGRect destRect) { return CGRectInset(destRect, -1, -1); }
arguments:@[src]
];
The kernel is very simple, sampling from the X coordinate equal to the src width - current coordinate:
float4 backwards(sampler image, destination dest)
{
float2 dc = dest.coord();
dc.x = image.size().x - dc.x;
return image.sample(image.transform(dc)));
}
When this runs on an image that is wider than 4096, tiling happens, with the result being that destRect is not the entire image and therefore the resulting output image is incorrect. If the ROI uses [src extent] instead of destRect, the result is correct, but this will lead to serious performance issues when src gets too large.
All of this makes sense to me. What I'd like to know is if there is a way to handle this filter's requirements for sampling from the entire source while still limiting the ROI to maintain performance? I think the answer is probably no within our current structure and performance limits. But I wanted to see if there's anything we're missing.
I am aware that the simple kernel above can be replaced with an affine transform, which is an option for backwards and upside-down mirroring. We have other kernels in this filter that perform mirroring of either half of the source image or one quadrant of the source image. In these cases, I suppose it might be possible (up to a point) to create a custom ROI that is only the portion of the source that is being mirrored. We have not attempted that yet.
Any thoughts/input appreciated, thanks!
Photos and Imaging
RSS for tagIntegrate still images and other forms of photography into your apps.
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Whenever I try to open Photos app on my iphone 14 pro, it immediately crashes .
I cannot access my photos. help me solve this!!
Hello!
I'm getting crash reports in PHPickerViewController for iOS 17 users only. Can someone point me into the right direction what could be the root cause in my case since it's related to PHPickerViewController?
Thread 0 name:
Thread 0 Crashed:
0 libsystem_kernel.dylib 0x00000001e7e9342c __pthread_kill + 8 (:-1)
1 libsystem_pthread.dylib 0x00000001fbc32c0c pthread_kill + 268 (pthread.c:1721)
2 libsystem_c.dylib 0x00000001a6d36ba0 abort + 180 (abort.c:118)
3 PhotoFoundation 0x00000001d2420280 -[PFAssertionPolicyAbort notifyAssertion:] + 68 (PFAssert.m:432)
4 PhotoFoundation 0x00000001d2420068 -[PFAssertionPolicyComposite notifyAssertion:] + 160 (PFAssert.m:259)
5 PhotoFoundation 0x00000001d242061c -[PFAssertionPolicyUnique notifyAssertion:] + 176 (PFAssert.m:292)
6 PhotoFoundation 0x00000001d241f7f4 -[PFAssertionHandler handleFailureInFunction:file:lineNumber:description:arguments:] + 140 (PFAssert.m:169)
7 PhotoFoundation 0x00000001d2420c74 _PFAssertFailHandler + 148 (PFAssert.m:127)
8 PhotosUI 0x0000000216b59e30 -[PHPickerViewController _handleRemoteViewControllerConnection:extension:extensionRequestIdentifier:error:completionHandler:] + 1356 (PHPicker.m:1502)
9 PhotosUI 0x0000000216b5a954 __66-[PHPickerViewController _setupExtension:error:completionHandler:]_block_invoke_3 + 52 (PHPicker.m:1454)
Crash report: 2024-09-05_18-27-56.7526_+0500-a953eaee085338a690ac1604a78de86e3e49d182.crash
Hello developer community.
I purchase recently my new iPhone 16 Pro Max; it is a premium device with great quality overall.
However, I am having a big trouble shotting in ProRaw MAX (48 mode) with native camera.
Just to be clear, the problem that i will describe do not happen in 3rd apps, such as ProCam; only with native camera.
When I use ProRaw Max, and take the photo, and watch the photo in the gallery the image can’t load and render properly. Even, when I maximize the image to the maximum I can see pixelated portions, defects and super low resolution and excessive denoise.
For comparison, this not occur with my previous iPhone 15 PM and/or when I capture photos from ProCam (same settings and configurations) in the 16PM. I proceed to take the photo, open the gallery and I see full of details, when zoomed to 100%.
I tried to format the phone, reinstall the software via my mac. Tried even to look at some forums to find if there’s someone with the same issue, the information available so far is very low.
I’m in contact with apple assistant from my country (Portugal), and they escalated this problem to the engineers. (that’s what I’ve been told).
They did all the tests remotely (via analysis and improvement’s) and they told me that my phone is perfect in the hardware department. I will wait for the next days to be contacted again.
I’m on iOS 18.0.1. (The last software available at this time).
I tried multiple 16PM, from friends, family and stores (more or less 10 units), and they all showed the exact same problematic.
I’m a professional photographer, so I find this frustrating and unacceptable.
I would appreciate any additional suggestion or information. Thank you!
Cannot add photos or files because they are bigger than 5Mb.
I'm updating my Photo Editing Extension to support HDR. To do this I set imageView.preferredImageDynamicRange = .high. But you can turn off the option to view HDR photos in the complete dynamic range in Settings > Photos. When you do that, open a photo, and tap the edit button, it does not appear in the full range as expected, but when you select my app from More > Extensions, it does appear in the complete dynamic range unexpectedly. I need to set imageView.preferredImageDynamicRange = .standard when View Full HDR is off, but I don't see any way to get that in my PHContentEditingController.
[[PHImageManager defaultManager]
requestAVAssetForVideo:asset
options:videoOptions
resultHandler:^(AVAsset *_Nullable avAsset,
AVAudioMix *_Nullable audioMix,
NSDictionary *_Nullable info) {
if ([avAsset isKindOfClass:[AVURLAsset class]]) {
AVURLAsset *urlAsset = (AVURLAsset *)avAsset;
NSURL *videoURL = urlAsset.URL;
mediaInfo[@"path"] = videoURL.absoluteString;
} else {
// Failed to get video asset
completion(nil);
}
}];```
Before iOS 18, i could able access AVAsset video using the method mentioned above with the url, but starting from the iOS 18 version, the following error appears
'You don’t have permission. - The AVPlayerItem instance has failed with the error code 257 and domain "NSCocoaErrorDomain".'
Hi,
My app allows users to share and view spatial photos.
For viewing spatial photos, I'm using a plane in a RealityView that has a camera index switch material node, which takes the stereo images as the inputs.
For sharing native spatial photos taken on the vision pro, prior to visionOS 2.0, I extract the stereo image pair and merge them into a single side-by-side image to upload to the app's backend.
However, since visionOS 2.0 introduced generating spatial photos from normal photos, I've been seeing some unexpected behaviours in my app, while on the other hand, they can be viewed correctly in the system Photos app:
Sometimes the extracted images have different size, the right image is smaller than the left image. See the first image in the google drive below, taken with iPhone 15 Pro.
Even if the image pair have the same size, when viewed in my app, it has some artefacts, especially around the edge of objects which are closer to the camera. See the second image in the google drive below, taken with iPhone 11.
Google drive link here:
https://drive.google.com/drive/folders/1UTfpxvO3-ChqshwfyzY5E_KCgk8VgUaa
I know that now Quicklook preview application can support viewing spatial photos now, but I would like to keep it the way I implemented in the app, for compatibility concerns.
Below is a code snippet that deals with the extraction. Please point out the correct way to extract stereo image pair from a generated spatial photo.
Happy to submit a code-level support request if more information is needed.
// the data is from photos picker item
let data = try await photo.loadTransferable(type: Data.self)
let source = CGImageSourceCreateWithData(data as CFData, nil)
let sbsImage = source.extractSpatialPhoto()
extension CGImageSource {
func extractSpatialPhoto() -> UIImage? {
guard let leftCGImage = extractSpatialImage(at: 0),
let rightCGImage = extractSpatialImage(at: 1)
else {
return nil
}
let leftImage = UIImage(ciImage: leftCGImage)
let rightImage = UIImage(ciImage: rightCGImage)
guard leftImage.size == rightImage.size else {
return nil
}
// merge left + right
let size = CGSize(width: leftImage.size.width * 2, height: leftImage.size.height)
UIGraphicsBeginImageContextWithOptions(size, true, 1.0)
leftImage.draw(in: CGRect(x: 0, y: 0, width: leftImage.size.width, height: leftImage.size.height))
rightImage.draw(in: CGRect(x: leftImage.size.width, y: 0, width: rightImage.size.width, height: rightImage.size.height))
let mergedImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return mergedImage
}
// not sure if this actually works
func extractSpatialImage(at index: Int) -> CIImage? {
guard let cgImage = CGImageSourceCreateImageAtIndex(self, index, nil) else {
return nil
}
var ciImage = CIImage(cgImage: cgImage)
if let properties = CGImageSourceCopyPropertiesAtIndex(self, index, nil) as? [String: Any],
let heifDictionary = properties[kCGImagePropertyHEIFDictionary as String] as? [String: Any],
let extrinsics = heifDictionary[kIIOMetadata_CameraExtrinsicsKey as String] as? [String: Any],
let position = extrinsics[kIIOCameraExtrinsics_Position as String] as? [Double]
{
// Default baseline is 64mm (0 for left camera, 0.064m for right camera)
let standardBaseline = 0.064
// Check if it's the right image (should be at [0.064, 0, 0])
let isRightImage = (index == 1)
let expectedPosition = isRightImage ? standardBaseline : 0.0
// Calculate the translation needed to align to standard baseline
let positionDelta = position[0] - expectedPosition
// Apply translation only if there's a mismatch in position
if positionDelta != 0 {
let transform = CGAffineTransform(translationX: CGFloat(positionDelta), y: 0)
ciImage = ciImage.transformed(by: transform)
}
}
return ciImage
}
}
I'm using UIKit to display a long list of large images inside a SwiftUI ScrollView and LazyHStack using UIViewControllerRepresentable. When an image is loaded, I'm using SDWebImage to load the image from the disk.
As the user navigates through the list and continues to load more images, more memory is used and is never cleared, even as the images are unloaded by the LazyHStack. Eventually, the app reaches the memory limit and crashes. This issue persists if I load the image with UIImage(contentsOfFile: ...) instead of SDWebImage.
How can I free the memory used by UIImage when the view is removed?
ScrollView(.horizontal, showsIndicators: false) {
LazyHStack(spacing: 16) {
ForEach(allItems) { item in
TestImageDisplayRepresentable(item: item)
.frame(width: geometry.size.width, height: geometry.size.height)
.id(item.id)
}
}
.scrollTargetLayout()
}
import UIKit
import SwiftUI
import SDWebImage
class TestImageDisplay: UIViewController {
var item: TestItem
init(item: TestItem) {
self.item = item
super.init(nibName: nil, bundle: nil)
}
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override func viewDidLoad() {
super.viewDidLoad()
let imageView = UIImageView(frame: CGRect(x: 0, y: 0, width: 200, height: 200))
imageView.center = view.center
view.addSubview(imageView)
imageView.sd_setImage(with: item.imageURL, placeholder: nil)
}
}
struct TestImageDisplayRepresentable: UIViewControllerRepresentable {
var item: TestItem
func makeUIViewController(context: Context) -> TestImageDisplay {
return TestImageDisplay(item: item)
}
func updateUIViewController(_ uiViewController: TestImageDisplay, context: Context) {
uiViewController.item = item
}
}